This invention relates generally to electrical switches, and more particularly it relates to a physical arrangement of two SPDT slide switches which--in combination--have a capability that is characteristic of more sophisticated momentary-on switches.
There are many occasions when it is desirable to foster the correct steering of a vehicle by a driver who cannot see where the vehicle is moving with respect to it surroundings. This is especially true when the vehicle is being backed into a parking spot, and the vehicle is so large that it obstructs the driver's view of the area into which the vehicle is backing. In such a case, it is desirable to have a communication device which will permit an observer who is at an advantageous position adjacent the vehicle (such as to the rear thereof) to send signals to the driver of the vehicle, in order to give said driver instructions concerning the way that the vehicle should be steered, etc. For example, the communication device may be used by an observer on foot to send instructions to the driver of a large recreation vehicle (such as a motor home) when the driver cannot see where his vehicle is going. Examples of signals which an observer would likely want to communicate to the driver are: (1) stop, (2) back up, (3) pull forward, (4) turn right, (5) turn left, (6) back up while turning left, (7) back up while turning right, (8) pull forward while turning left, and (9) pull forward while turning right. While it would obviously be possible to permit an observer to communicate with the driver with a pair of radios, such as the popular "Walkie-Talkies" which operate in the Citizens Band range, such radios are relatively expensive--if they are of a quality to provide reliable and interference-free service. Also, at the time that a certain driver needs guidance information for his vehicle, some other party may be broadcasting on the only available channel (e.g., channel 14); so the driver must wait for his turn in order to have a clear channel to communicate with his observer. Accordingly, there has been a need for a reliable--but economical--means for permitting private and readily available communication between an observer and the vehicle driver.
Another difficulty has been that those persons who are adults and should know their right hand from their left have been known sometimes to mistakenly say "right" when they meant left. Also, there are many children who do not have the left-right relationship well settled in their minds, such that they do not know how to issue correct vocal instructions; but even young children are usually capable of seeing whether or not a car is correctly approaching a trailer, and they could give meaningful information to the driver based on spatial relationships--if they only had some way to convey what they see. Hence, it is an object of this invention to provide a switching device which does not rely on spoken language and which should be useful for most any observer to give instructions to the driver of a vehicle as he attempts to move it towards a desired target.
One more object is to provide a momentary-off capability for a basic single-pole, double-throw slide switch.
A further object is to provide a technique for ganging two single-pole, double-throw switches 90.degree. apart so that they will provide a centered rest position for a central arm between four possible positions along two orthogonal axes.